The difference between the short stroke and long stroke M-B blocks is the height. Going back to original 116(3.5)and 117(4.5) engines, the blocks were about 30mm different in height. The get the longer stroke into a shorter hole isn't possible...that is the basic difference between a 3.5 and a 4.5 or a 3.8 and a 5.0 block. One is taller than the other.
Regards,
Randy D.

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W.R.Durrance
ASE Master Tech
Mercedes Tech 20 Years
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